The SLI team used a heavy vice to hold the 4" Mad Cow Black Brant for ground testing. For the larger 5" scratch built rocket, they strapped the rocket to two cinder blocks, protecting the rocket with towels (the vice did not open wide enough for the 5" body tube - see attached photos).
To set off the charges for ground testing, we assembled the rocket as if it were to be launched except with an empty avionics bay. We replaced the electronics with a long wire pair run out of the avionics bay through an altimeter vent hole, or the safety switch hole. To fire the charge, we just attached a 9 volt battery across the two wires.
We tested the altimeters separately, replacing the e-matches with incandescent Christmas Tree light bulbs and either running them in a "vacuum chamber" (converted pickle jar) or connecting the electronics to the computer via the USB cable and running the simulation using the software supplied for the altimeter.
There are videos of the black powder testing of the 4" Black Brant in the middle of the page at: http://aiaaocrocketry.org/?page_id=343 as well as the pickle jar testing near the bottom of that page.
Bob Koepke----- Original Message ----- From: "Bob Brown" <cineflex@xxxxxxx>
To: <roc-chat@xxxxxxxxxxxxx> Sent: Thursday, June 14, 2012 4:48 PM Subject: [roc-chat] Re: Dual Deployment advice
Thanks everyone for your deployment tips. Really helpful. The rocket in question is a Madcow fiberglass Black Brant. 3.9" Regarding ground testing. What methods are used to "hold" the rocket? What is the best way to set off the deployments on my altimeter when on the ground? Thanks again.Bob On Jun 14, 2012, at 12:24 AM, Mike Riss wrote:--- On Wed, 6/13/12, Bob Brown <cineflex@xxxxxxx> wrote:. . .but am not sure of a design for holding and igniting the BP. Any advice about these or other systems would be appreciatedHere's some info on do-it-yourself methods: http://www.info-central.org/?article=302 http://www.wimpyrockets.com/page16.html http://www.thefintels.com/aer/rocketelectronics.htm And, I'll add to the question about which kit: and what altitudes? Mike -- ROC-Chat mailing list roc-chat@xxxxxxxxxxxxx http://www.freelists.org/list/roc-chatBob Brown http://us.imdb.com/name/nm0113141/ http://www.tripoli.org/ #9186-L3 -- ROC-Chat mailing list roc-chat@xxxxxxxxxxxxx http://www.freelists.org/list/roc-chat
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